Helmut Marko has claimed that there are "still some facts" that Red Bull are looking into after Aston Martin's latest upgrade package was deemed legal by the FIA.
The modifications made to the AMR22 for the Spanish Grand Prix have drawn comparisons to the RB18, particularly in regards to the sidepods and engine cover.
An investigation was carried out by the FIA after it was observed that some of the features "resembled those of another competitor", and a subsequent statement from the governing body confirmed that Aston Martin have been cleared of any wrongdoing.
Red Bull responded with their own statement in which they continued to raise concerns about the situation.
"Should any transfer of IP have taken place, that would clearly be a breach of regulations and would be a serious concern," the statement concluded.
Marko demands answers over "unbelievable copy"
Red Bull boss Christian Horner has made his feelings clear over the matter, having labelled the modifications as being a "clone" of the RB18.
Team advisor Marko is similarly critical of the situation, and has demanded answers over what he has called an "unbelievable copy".
"It must now be clarified how this unbelievable copy came about," he told Sky Sport Germany.
"Copying is not forbidden. But you also have to take into account that seven people were poached from us and that our chief aerodynamicist [Dan Fallows] was drawn to Aston Martin with a disproportionately high fee."
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Do Red Bull have evidence of any wrongdoing?
Furthermore, Marko has suggested that Red Bull have "evidence" that they are still looking into.
"There are still some facts that we are looking into. We will look into it in detail," he added.
"It's not just Dan Fallows. There is evidence that data was downloaded.
"Is it possible to copy without documentation and then manage such a detailed copy of our car?"
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